
// LCR 104.组合总数IV
class Solution {
public:
    int combinationSum4(vector<int>& nums, int target) {
        int n = nums.size();
        vector<double> dp(target + 1);
        dp[0] = 1;
        for(int i = 1 ; i <= target ; i++)
        {
            for(auto& x : nums)
                if(i >= x) dp[i] += dp[i - x];
        }
        return dp[target];
    }
}; 